JP2007216082A - Catalyst for decomposing ammonia and method for treating ammonia - Google Patents
Catalyst for decomposing ammonia and method for treating ammonia Download PDFInfo
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Abstract
Description
本発明は、各種排ガス中に含まれるアンモニアを無害な窒素に分解するアンモニア分解触媒、及びそのアンモニア分解触媒を用いた排ガス中のアンモニア処理方法に関する。 The present invention relates to an ammonia decomposition catalyst that decomposes ammonia contained in various exhaust gases into harmless nitrogen, and a method for treating ammonia in exhaust gases using the ammonia decomposition catalyst.
火力発電設備、下水処理設備、アミン製造設備、食品製造設備、し尿処理設備、コークス炉製造設備などから排出される排ガス中のアンモニアは有害物質であり、これら設備の配管を腐食するなど悪影響が大きい。そのため、これらの排ガス中のアンモニアを効率よく除去する技術の開発が望まれている。 Ammonia in exhaust gas discharged from thermal power generation equipment, sewage treatment equipment, amine production equipment, food production equipment, human waste treatment equipment, coke oven production equipment, etc. is a harmful substance, and it has a bad influence such as corroding the piping of these equipment. . Therefore, development of a technique for efficiently removing ammonia in these exhaust gases is desired.
排ガス中のアンモニアを除去する方法として、例えば、特公昭５７−０５８２１３号公報、特開平０２−１９８６３８号公報、特公平０６−００４１３８号公報、特開平０７−３２８４４０号公報などには、白金、パラジウムなどの貴金属をアルミナ、シリカ、チタニアなどの担体に担持した貴金属系触媒を用いる方法や、銅、ニッケル、コバルトなどの酸化物を触媒活性成分として分散担持したアンモニア分解触媒を用いる方法が提案されている。 As a method for removing ammonia in exhaust gas, for example, Japanese Patent Publication No. 57-058213, Japanese Patent Application Laid-Open No. 02-198638, Japanese Patent Publication No. 06-004138, Japanese Patent Application Laid-Open No. 07-328440, etc. include platinum, palladium A method using a noble metal catalyst in which a noble metal such as alumina, silica or titania is supported and a method using an ammonia decomposition catalyst in which an oxide such as copper, nickel or cobalt is dispersed and supported as a catalyst active component have been proposed. Yes.
しかし、上記した従来のアンモニア分解触媒は、高温条件下やアンモニア濃度に対する酸素過剰条件下では、アンモニアの酸化によって大気汚染物質である窒素酸化物ＮＯｘが多量に発生するという欠点があった。しかも、白金やパラジウムなどの貴金属系触媒は、コストが高くなるなどの問題もあった。また、銅やニッケルなどの卑金属酸化物系触媒は、低温での活性が低く、その場合に大気汚染物質であるＮＯｘやＮ２Ｏの発生を招くという問題があった。 However, the conventional ammonia decomposition catalyst described above has a drawback that a large amount of nitrogen oxide NOx, which is an air pollutant, is generated due to oxidation of ammonia under high temperature conditions or oxygen excess conditions with respect to ammonia concentration. In addition, noble metal catalysts such as platinum and palladium have a problem of high cost. In addition, base metal oxide catalysts such as copper and nickel have low activity at low temperatures, and in this case, there is a problem in that NOx and N 2 O, which are air pollutants, are generated.
そこで、アンモニア分解時における窒素酸化物ＮＯｘの副生を防止するため、例えば、特開平０５−１４６６３４号公報、特開平０８−１３１８３２号公報、特開２００３−２４７８４号公報、特開２００３−２０００５０号公報には、チタン、バナジウム、タングステン、モリブデンなどの脱硝触媒成分と、白金、パラジウム、ロジウムなどの酸化触媒成分とを組み合わせたアンモニア分解触媒が提案されている。 Therefore, in order to prevent the generation of nitrogen oxides NOx during ammonia decomposition, for example, Japanese Patent Laid-Open Nos. 05-146634, 08-131832, 2003-24784, and 2003-200050 are disclosed. The publication proposes an ammonia decomposition catalyst that combines a denitration catalyst component such as titanium, vanadium, tungsten, and molybdenum and an oxidation catalyst component such as platinum, palladium, and rhodium.
しかしながら、このようなアンモニア分解触媒は、酸化触媒成分が貴金属を含むため高価であるという問題があった。そのため、貴金属を含まず安価であって、大気汚染物質であるＮＯｘやＮ２Ｏの発生の副生を抑えると共に、アンモニアを効率よく分解することができるアンモニア分解触媒の提供が望まれていた。 However, such an ammonia decomposition catalyst has a problem that it is expensive because the oxidation catalyst component contains a noble metal. Therefore, it has been desired to provide an ammonia decomposition catalyst that does not contain precious metals, is inexpensive, suppresses the generation of NOx and N 2 O, which are air pollutants, and can efficiently decompose ammonia.
本発明は、このような従来の事情に鑑み、大気汚染のもととなる窒素酸化物のＮＯｘやＮ２Ｏの副生を極力抑え、排ガス中のアンモニアを効率よく窒素に分解除去することのできるアンモニア分解触媒、及びその触媒を使用したアンモニア処理方法を提供することを目的とする。 In view of such conventional circumstances, the present invention suppresses as much as possible NOx and N 2 O by-products of nitrogen oxides that cause air pollution, and efficiently decomposes and removes ammonia in exhaust gas into nitrogen. It is an object of the present invention to provide an ammonia decomposition catalyst that can be used and an ammonia treatment method using the catalyst.
上記目的を達成するため、本発明が提供するアンモニア分解触媒は、ＳｉＯ２／Ａｌ２Ｏ３モル比が１０以上であるゼオライトと、酸化マンガンとを混合したことを特徴とするものである。上記本発明のアンモニア分解触媒においては、前記酸化マンガンの含有量は触媒全体に対し５〜８０重量％であることが好ましい。 In order to achieve the above object, the ammonia decomposition catalyst provided by the present invention is characterized in that a zeolite having a SiO 2 / Al 2 O 3 molar ratio of 10 or more and manganese oxide are mixed. In the ammonia decomposition catalyst of the present invention, the manganese oxide content is preferably 5 to 80% by weight based on the whole catalyst.
また、本発明が提供するアンモニア処理方法は、排ガス中のアンモニアを触媒により分解して除去するアンモニア処理方法であって、上記本発明のアンモニア分解触媒、即ち、ＳｉＯ２／Ａｌ２Ｏ３モル比が１０以上であるゼオライトと、酸化マンガンとを混合したことを特徴とするアンモニア分解触媒を用いることを特徴とする。 The ammonia treatment method provided by the present invention is an ammonia treatment method in which ammonia in exhaust gas is decomposed and removed by a catalyst, and the ammonia decomposition catalyst of the present invention, that is, a SiO 2 / Al 2 O 3 molar ratio. Is characterized by using an ammonia decomposition catalyst characterized by mixing a zeolite having 10 or more with manganese oxide.
本発明によれば、高温や低温などの温度条件にかかわらず、また排ガス中のアンモニア濃度に対して酸素過剰の条件下であっても、大気汚染のもととなるＮＯやＮＯ２のような窒素酸化物ＮＯｘ及びＮＯの副生を極力抑えながら、排ガス中のアンモニアを効率よく窒素に分解することができる、貴金属を含まない安価なアンモニア分解触媒を提供することができる。 According to the present invention, regardless of the temperature conditions such as high or low temperature, also be oxygen excess conditions to ammonia concentration in the exhaust gas, such as NO and NO 2 as a source of air pollution It is possible to provide an inexpensive ammonia decomposition catalyst that does not contain a noble metal and can efficiently decompose ammonia in exhaust gas into nitrogen while suppressing by-products of nitrogen oxides NOx and NO as much as possible.
従って、本発明のアンモニア分解触媒を用いることによって、火力発電設備、下水処理設備、アミン製造設備、食品製造設備、し尿処理設備、コークス炉製造設備などから排出される各種排ガスを処理して、その排ガス中に含まれるアンモニアを無害な窒素に分解することができ、しかも大気汚染のもととなるＮＯやＮＯ２のような窒素酸化物ＮＯｘ、及びＮ２Ｏの副生を抑えることができる。 Therefore, by using the ammonia decomposition catalyst of the present invention, various exhaust gases discharged from thermal power generation equipment, sewage treatment equipment, amine production equipment, food production equipment, human waste treatment equipment, coke oven production equipment, etc. are treated, and Ammonia contained in the exhaust gas can be decomposed into harmless nitrogen, and nitrogen oxides NOx such as NO and NO 2 that cause air pollution and N 2 O by-product can be suppressed.
本発明のアンモニア分解触媒は、ゼオライトと酸化マンガンとを混合したものである。酸化マンガンの含有量は触媒全体の５〜８０重量％であり、１０〜６０重量％が好ましい。酸化マンガンの含有量が５重量％未満の場合は、十分なアンモニア分解能が得られない。酸化マンガンの含有量の増加に伴ってアンモニア分解能も向上するが、８０重量％を超えるとアンモニアの酸化によって大気汚染物質であるＮＯｘやＮ２Ｏの副生が顕著に増加するため好ましくない。尚、ゼオライトと酸化マンガンの混合方法に関しては、特に制約はなく、両者を十分に混合できる方法であればよい。 The ammonia decomposition catalyst of the present invention is a mixture of zeolite and manganese oxide. The content of manganese oxide is 5 to 80% by weight of the whole catalyst, and preferably 10 to 60% by weight. When the content of manganese oxide is less than 5% by weight, sufficient ammonia resolution cannot be obtained. As the manganese oxide content increases, the ammonia degrading ability is also improved. However, if it exceeds 80% by weight, the by-production of NOx and N 2 O, which are air pollutants, is remarkably increased due to the oxidation of ammonia. In addition, there is no restriction | limiting in particular regarding the mixing method of a zeolite and manganese oxide, What is necessary is just the method which can fully mix both.
使用するゼオライトは、ＳｉＯ２／Ａｌ２Ｏ３モル比が１０以上であるものが好ましく、より十分な耐久性が得られるという点では１０〜２００の範囲が更に好ましい。また、ゼオライトの種類については、特に制限はなく、βゼオライト、フェリエライト、モルデナイト、ＺＳＭ−５などが使用できる。これらのゼオライトの製造方法については、特に限定されるものではない。また、酸化マンガンとしては、二酸化マンガンが好ましい。 The zeolite used preferably has a SiO 2 / Al 2 O 3 molar ratio of 10 or more, and is more preferably in the range of 10 to 200 in terms of obtaining more sufficient durability. Moreover, there is no restriction | limiting in particular about the kind of zeolite, (beta) zeolite, ferrierite, mordenite, ZSM-5, etc. can be used. The method for producing these zeolites is not particularly limited. Moreover, as manganese oxide, manganese dioxide is preferable.
本発明のアンモニア分解触媒であるゼオライトと酸化マンガンの混合物は、従来知られている成形方法により成形することができる。成形されたアンモニア分解触媒の形状は、特に限定されず、例えば、球状、ハニカム状、ペレット状など、種々の形状であってよい。これらの形状並びに大きさなどは、使用条件に応じて任意に選択すればよい。また、排ガスの流れ方向に対して多数の貫通孔を有する耐火性一体構造の支持基体の表面に、ウォッシュコート法などによりアンモニア分解触媒を被覆することも可能である。 The mixture of zeolite and manganese oxide, which is the ammonia decomposition catalyst of the present invention, can be molded by a conventionally known molding method. The shape of the formed ammonia decomposition catalyst is not particularly limited, and may be various shapes such as a spherical shape, a honeycomb shape, and a pellet shape. These shapes and sizes may be arbitrarily selected according to use conditions. It is also possible to coat an ammonia decomposition catalyst by a wash coat method or the like on the surface of a support base having a fireproof integrated structure having a large number of through holes in the flow direction of the exhaust gas.
本発明のアンモニア分解触媒を排ガスと接触させることによって、排ガス中のアンモニアを酸化分解して除去することができる。アンモニアを含む排ガスを処理する際のガス空間速度（ＳＶ）については、特に限定されるものではないが、ＳＶ１,０００〜１００,０００／ｈの範囲とすることが好ましい。また、反応温度は２００〜５００℃程度でよく、特に３００〜４００℃が好ましい。 By bringing the ammonia decomposition catalyst of the present invention into contact with exhaust gas, ammonia in the exhaust gas can be oxidized and removed. Although it does not specifically limit about the gas space velocity (SV) at the time of processing the waste gas containing ammonia, It is preferable to set it as the range of SV1,000-100,000 / h. The reaction temperature may be about 200 to 500 ° C, and 300 to 400 ° C is particularly preferable.
［本発明のアンモニア分解触媒の調製］
ＳｉＯ２／Ａｌ２Ｏ３モル比が２０のモルデナイト粉末１０ｇと、二酸化マンガン粉末４.３ｇ（３０重量％）をメノー乳鉢にて物理混合した。この混合物を加圧成形した後、粉砕して粒度を３５０〜５００μｍに整粒し、本発明による触媒１とした。上記と同様にゼオライト粉末と二酸化マンガン粉末を混合する際に、ＳｉＯ２／Ａｌ２Ｏ３モル比１３のモルデナイト粉末を用いた以外は上記触媒１の場合と同様にして、触媒２を得た。また、ＳｉＯ２／Ａｌ２Ｏ３モル比９０のモルデナイト粉末を用いた以外は上記触媒１の場合と同様にして、触媒３を得た。
[Preparation of ammonia decomposition catalyst of the present invention]
10 g of mordenite powder having a SiO 2 / Al 2 O 3 molar ratio of 20 and 4.3 g (30% by weight) of manganese dioxide powder were physically mixed in a menor mortar. This mixture was pressure-molded and then pulverized to adjust the particle size to 350 to 500 μm, thereby obtaining catalyst 1 according to the present invention. When mixing zeolite powder and manganese dioxide powder in the same manner as above, catalyst 2 was obtained in the same manner as in catalyst 1 except that a mordenite powder having a SiO 2 / Al 2 O 3 molar ratio of 13 was used. Further, except for using the mordenite powder SiO 2 / Al 2 O 3 molar ratio of 90 in the same manner as in the case of the catalyst 1, to obtain catalyst 3.
上記と同様にゼオライト粉末と二酸化マンガン粉末を混合する際に、二酸化マンガン含有量を触媒全体の５重量％とした以外は上記触媒１の場合と同様にして、本発明の触媒４を得た。また、二酸化マンガン含有量を触媒全体の６０重量％、８０重量％とした以外は上記触媒１の場合と同様にして、それぞれ本発明の触媒５と触媒６を得た。 In the same manner as described above, the catalyst 4 of the present invention was obtained in the same manner as in the case of the catalyst 1 except that when the zeolite powder and the manganese dioxide powder were mixed, the manganese dioxide content was changed to 5% by weight of the total catalyst. Further, Catalyst 5 and Catalyst 6 of the present invention were obtained in the same manner as in the case of Catalyst 1 except that the manganese dioxide content was changed to 60% by weight and 80% by weight of the whole catalyst.
上記と同様にゼオライト粉末と二酸化マンガン粉末を混合する際に、モルデナイト粉末に代えてＳｉＯ２／Ａｌ２Ｏ３モル比１５０のβゼオライト粉末を用いた以外は上記触媒１の場合と同様にして、本発明の触媒７を得た。同じくモルデナイト粉末に代えてＳｉＯ２／Ａｌ２Ｏ３モル比８０のＺＳＭ−５粉末を用いた以外は上記触媒１の場合と同様にして、触媒８を得た。更に、同じくモルデナイト粉末に代えてＳｉＯ２／Ａｌ２Ｏ３モル比２０のフェリエライト粉末を用いた以外は上記触媒１の場合と同様にして、触媒９を得た。 When mixing zeolite powder and manganese dioxide powder in the same manner as above, except that β zeolite powder having a SiO 2 / Al 2 O 3 molar ratio of 150 was used instead of the mordenite powder, the same as in the case of the catalyst 1 above, A catalyst 7 of the present invention was obtained. Similarly, catalyst 8 was obtained in the same manner as in the case of catalyst 1 except that ZSM-5 powder having a SiO 2 / Al 2 O 3 molar ratio of 80 was used instead of mordenite powder. Further, a catalyst 9 was obtained in the same manner as in the case of the catalyst 1 except that ferrilite powder having a SiO 2 / Al 2 O 3 molar ratio of 20 was used instead of the mordenite powder.
［比較例のアンモニア分解触媒の調製］
上記実施例の触媒と同様にゼオライト粉末と二酸化マンガン粉末を混合した触媒を調製したが、その際に二酸化マンガン含有量を触媒全体の１重量％とした以外は上記触媒1の場合と同様にして、比較例の触媒Ｃ１を得た。また、同じく二酸化マンガン含有量を触媒全体の９０重量％とした以外は上記触媒１の場合と同様にして、比較例の触媒Ｃ２を得た。
[Preparation of Comparative Example Ammonia Decomposition Catalyst]
A catalyst in which zeolite powder and manganese dioxide powder were mixed was prepared in the same manner as the catalyst of the above example, except that the manganese dioxide content was 1% by weight of the total catalyst. A catalyst C1 of Comparative Example was obtained. Similarly, Comparative Example Catalyst C2 was obtained in the same manner as in Catalyst 1 except that the manganese dioxide content was changed to 90% by weight of the total catalyst.
また、上記と同様にゼオライト粉末と二酸化マンガン粉末を混合する際に、モルデナイト粉末に代えてＳｉＯ２／Ａｌ２Ｏ３モル比１５０のβゼオライト粉末を用い、且つ二酸化マンガン含有量を触媒全体の９０重量％とした以外は上記触媒１の場合と同様にして、比較例の触媒Ｃ３を得た。同じくモルデナイト粉末に代えてＳｉＯ２／Ａｌ２Ｏ３モル比８０のＺＳＭ−５粉末を用い、且つ二酸化マンガン含有量を触媒全体の１重量％とした以外は上記触媒１の場合と同様にして、比較例の触媒Ｃ４を得た。同じくモルデナイト粉末に代えてＳｉＯ２／Ａｌ２Ｏ３モル比２０のフェリエライト粉末を用い、且つ二酸化マンガン含有量を触媒全体の１重量％とした以外は上記触媒１の場合と同様にして、比較例の触媒Ｃ５を得た。 In addition, when mixing zeolite powder and manganese dioxide powder in the same manner as described above, β zeolite powder having a SiO 2 / Al 2 O 3 molar ratio of 150 was used instead of mordenite powder, and the manganese dioxide content was 90% of the total catalyst. A catalyst C3 of a comparative example was obtained in the same manner as in the case of the catalyst 1 except that the weight was changed. Similarly, in place of the mordenite powder, a ZSM-5 powder having a SiO 2 / Al 2 O 3 molar ratio of 80 was used, and the manganese dioxide content was set to 1% by weight of the whole catalyst. A comparative catalyst C4 was obtained. Similarly, in place of the mordenite powder, a ferrilite powder having a SiO 2 / Al 2 O 3 molar ratio of 20 was used, and the manganese dioxide content was changed to 1% by weight of the total catalyst, and the same as in the case of the catalyst 1 above. Example catalyst C5 was obtained.
更に、１５００ｇのイオン交換水に硝酸マンガン（II）六水和物１００ｇを溶解し、この溶液を撹拌しながらｐＨ８となるように水酸化ナトリウム水溶液を流し込み、共沈物（水酸化物）を生成させた。その後、１時間の熟成を行い、上記共沈物をろ過及び洗浄し、１１０℃で通風乾燥した後、大気中にて５００℃で３時間焼成することによって、二酸化マンガンのみからなる比較例の触媒Ｃ６を得た。 Further, 100 g of manganese (II) nitrate hexahydrate is dissolved in 1500 g of ion-exchanged water, and an aqueous solution of sodium hydroxide is poured into the solution so that the pH is 8 while stirring, thereby forming a coprecipitate (hydroxide). I let you. Thereafter, aging is performed for 1 hour, the coprecipitate is filtered and washed, dried by ventilation at 110 ° C., and then calcined at 500 ° C. for 3 hours in the atmosphere, whereby a comparative catalyst consisting only of manganese dioxide. C6 was obtained.
［触媒の評価試験］
上記した本発明の触媒１〜９及び比較例の触媒Ｃ１〜Ｃ６について、アンモニア分解能を評価した。即ち、各触媒をそれぞれ内径６ｍｍの石英ガラス製反応管に充填して触媒体を形成し、これを常圧固定床流通反応装置に装着した。この反応管内に、モデル排ガスとしてＮＨ３：５,０００ｐｐｍ、Ｏ２：１７％、Ｈ２Ｏ：１２％、残部：Ｎ２からなる混合ガスを、ガス温度３５０℃、空間速度５０,０００／ｈで通過させ、アンモニアの分解処理を行った。得られた結果を、各触媒の構成と共に下記表１に示す。
[Catalyst evaluation test]
The ammonia decomposability was evaluated for the catalysts 1 to 9 of the present invention and the catalysts C1 to C6 of the comparative examples. That is, each catalyst was filled in a quartz glass reaction tube having an inner diameter of 6 mm to form a catalyst body, which was attached to an atmospheric pressure fixed bed flow reactor. In this reaction tube, as a model exhaust gas, a mixed gas consisting of NH 3 : 5,000 ppm, O 2 : 17%, H 2 O: 12% and the balance: N 2 was gas temperature 350 ° C., space velocity 50,000 / h. Then, ammonia was decomposed. The obtained results are shown in Table 1 below together with the structure of each catalyst.
尚、アンモニア分解率は下記数式１、ＮＯｘ生成率は下記数式２、及びＮ２Ｏ生成率は下記数式３に従って算出した。
［数式１］
アンモニア分解率(％)＝(入口ＮＨ３濃度−出口ＮＨ３濃度)／入口ＮＨ３濃度×１００
［数式２］
ＮＯｘ生成率(％)＝(出口ＮＯ濃度＋出口ＮＯ２濃度)／入口ＮＨ３濃度×１００
［数式３］
Ｎ２Ｏ生成率(％)＝出口Ｎ２Ｏ濃度×２／入口ＮＨ３濃度×１００
The ammonia decomposition rate was calculated according to the following formula 1, the NOx generation rate was calculated according to the following formula 2, and the N 2 O generation rate was calculated according to the following formula 3.
[Formula 1]
Ammonia decomposition rate (%) = (Inlet NH 3 concentration−Outlet NH 3 concentration) / Inlet NH 3 concentration × 100
[Formula 2]
NOx generation rate (%) = (outlet NO concentration + outlet NO 2 concentration) / inlet NH 3 concentration × 100
[Formula 3]
N 2 O production rate (%) = Outlet N 2 O concentration × 2 / Inlet NH 3 concentration × 100
上記表の結果から分かるように、ゼオライトと５〜８０重量％の二酸化マンガンを混合した本発明の触媒１〜９は、いずれも９０％を超えるアンモニア分解率で排ガス中のアンモニアを窒素に分解することができた。しかも、アンモニアに対して酸素過剰の条件下であっても、大気汚染物質である窒素酸化物ＮＯｘやＮ２Ｏの副生を顕著に抑制することができた。 As can be seen from the results in the above table, the catalysts 1 to 9 of the present invention mixed with zeolite and 5 to 80% by weight of manganese dioxide all decompose ammonia in the exhaust gas into nitrogen at an ammonia decomposition rate exceeding 90%. I was able to. In addition, even under conditions where oxygen is excessive with respect to ammonia, by-products of nitrogen oxides NOx and N 2 O, which are air pollutants, can be remarkably suppressed.
一方、比較例の触媒Ｃ１、Ｃ４、Ｃ５は、いずれもゼオライトと混合した二酸化マンガンの含有量が５重量％未満であるため、アンモニア分解率が著しく低下した。また、比較例の触媒Ｃ２、Ｃ３は逆に二酸化マンガンの含有量が８０重量％を超えるため、アンモニア分解率は高いが、ＮＯｘやＮ２Ｏの副生が極めて多くなった。更に、比較例の触媒Ｃ６は二酸化マンガンのみであるため、ＮＯｘやＮ２Ｏの副生が更に大幅に増加した。
On the other hand, the catalysts C1, C4, and C5 of the comparative examples all had a manganese dioxide content of less than 5% by weight mixed with zeolite, so that the ammonia decomposition rate was significantly reduced. In contrast, the catalysts C2 and C3 of the comparative example had a manganese dioxide content exceeding 80% by weight, and thus the ammonia decomposition rate was high, but NOx and N 2 O by-products were extremely increased. Further, since the catalyst C6 of the comparative example is only manganese dioxide, NOx and N 2 O by-products are further greatly increased.
Claims (3)
An ammonia treatment method for decomposing and removing ammonia in exhaust gas with a catalyst, wherein the ammonia decomposition catalyst according to claim 1 or 2 is used.
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| JP2006035900A JP2007216082A (en) | 2006-02-14 | 2006-02-14 | Catalyst for decomposing ammonia and method for treating ammonia |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2525721A (en) * | 2014-02-27 | 2015-11-04 | Johnson Matthey Plc | Exhaust system having N20 catalyst in EGR circuit |
| WO2020138327A1 (en) | 2018-12-27 | 2020-07-02 | 日揮ユニバーサル株式会社 | Catalyst for ammonia decomposition and exhaust gas treatment method |
-
2006
- 2006-02-14 JP JP2006035900A patent/JP2007216082A/en not_active Withdrawn
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2525721A (en) * | 2014-02-27 | 2015-11-04 | Johnson Matthey Plc | Exhaust system having N20 catalyst in EGR circuit |
| GB2525721B (en) * | 2014-02-27 | 2016-12-28 | Johnson Matthey Plc | Exhaust system having N20 catalyst in EGR circuit |
| US9587591B2 (en) | 2014-02-27 | 2017-03-07 | Johnson Matthey Public Limited Company | Exhaust system having N2O catalyst in EGR circuit |
| WO2020138327A1 (en) | 2018-12-27 | 2020-07-02 | 日揮ユニバーサル株式会社 | Catalyst for ammonia decomposition and exhaust gas treatment method |
| KR20210106509A (en) | 2018-12-27 | 2021-08-30 | 니키 유니바사루 가부시키가이샤 | Catalyst for ammonia decomposition and treatment method of exhaust gas |
| US11911747B2 (en) | 2018-12-27 | 2024-02-27 | Nikki-Universal Co., Ltd. | Catalyst for ammonia decomposition and exhaust gas treatment method |
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